<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // await 后面不一定跟promise
        //await会将函数阻塞,会优先执行同步不耗时的任务 再去执行await完毕之后的内容
        async function show(){
            console.log("start");
            await mid();
            console.log("end");
        }
        async function mid(){
            console.log("mid");
            // return 1
        }
        show()
        console.log("a1");
        //star mid a1 end
    </script>
</body>
</html>